Conventional molten metal casting methods used to produce shroud segments require that the casting core used to form internal cooling passages inside the shroud segment be made out of refractory or high temperature resistance materials, such as ceramic, in order not to be damaged or destroyed when the molten casting material is poured into the mold to form the shroud segment. There are a series of disadvantages (cost, fragile, extraction after cast) and limitations (shape and size) associated to the use of ceramic cores and the like. Indeed, ceramic cores are relatively costly to produce and fragile. Several operations, such as chemical leaching, may be required to dissolve the ceramic insert and clean the internal cooling cavity left by the dissolved ceramic insert in the cast turbine shroud segment, resulting in additional manufacturing costs. The use of ceramic also imposes some restrictions to the designers in terms of shape and size of the casting core.
There is thus a need for a new shroud segment manufacturing method.